(68) باب الأَشْهُرِ الْحُرُمِ
Narrated AbuBakrah:
The Prophet (ﷺ) gave a sermon during his hajj and said: Time has completed a cycle and assumed the form of the day when Allah created the heavens and the earth. The year contains twelve months of which four are sacred, three of them consecutive, viz. Dhul-Qa'dah, Dhul-Hijjah and Muharram and also Rajab of Mudar which comes between Jumadah and Sha'ban.
Reference: Sunan Abi Dawud 1947
In-book reference: Book 11, Hadith 227
English translation: Book 10, Hadith 1942